| 摘要 |
Well bore drilling shock absorber device for absorbing drill bit vibratory displacement shock, especially in elevated temperature formation drilling, in which the pair of slidably associated elements, e.g. telescoping inner mandrel and outer housing, interconnected for common rotation for drilling purposes and relative reciprocal displacement longitudinally for shock absorbing purposes, and adapted to be interposed operatively between a drill string thereabove and a drill bit therebelow, is provided with longitudinally resilient mechanical tension shock absorbing means, e.g. linear means or cable means such as wire rope, rods, tubes, chains, etc., of metal or plastic, interposed therebetween and operatively interconnecting the elements in longitudinally resilient suspension relation, whereby to absorb, suppress and even isolate, under tension, and substantially independently of the ambient thermal and mechanical, pneumatic, hydraulic and/or hydrostatic pressure conditions, dynamic longitudinal stress or load corresponding to vibratory drill bit displacement shock acting through one of the elements, optionally with a portion of the interior of the device in restricted open flow communication with the ambient exterior drilling fluid for exerting a counterpressure operatively thereon, and preferably with such shock absorbing means disposed in a sealed chamber defined between such elements and containing a lubricant, optionally with pressure balancing means being provided for maintaining such chamber in indirect pressure flow-communication with the ambient external pressure.
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